PARIS: Advertising expenditure is likely to increase worldwide both this year and next, despite the challenging economic climate being experienced in many markets, new figures suggest.

ZenithOptimedia, part of Publicis Groupe, argued in its latest forecast that adspend levels should climb by 3.5% in 2011 to a value of $464bn, and then by 4.7% to $486bn in 2012.

The firm said the "quadrennial effect" resulting from major events like the US Presidential elections, European football championships and Olympic Games, alongside a recovery in Japan, should yield an extra $7bn in revenue across 2012 as a whole.

"Advertisers are in a very different position now than they were at the start of the last downturn in 2008. In general, advertisers have built up large cash reserves and – thanks to exceptionally low interest rates in the developed world – are earning very little interest on this cash," ZenithOptimedia's study said.

Looking longer term, the US will be worth $155bn in 2011 and $173bn by 2014. These figures stood at $45bn and $49bn respectively for Japan, while China is pegged to see a lift from $30bn to $46bn.

Meanwhile, GroupM, the media arm of WPP Group, predicted global ad revenue should expand by 5% in 2011, hitting $467bn. Totals for 2012 were placed at $522bn, equating to a 6.8% annual improvement.

"Japan's advertising recovery has proved substantially more vigorous and resilient than we forecast in our mid-year report," Adam Smith, GroupM's futures director, said.

Looking specifically at the US, the company estimated that spending was likely to reach $147bn in 2011, equivalent to a 3.3% increase year on year, before witnessing a 4% leap in 2012, to $153bn.

New media channels like the web and mobile are due to gain further momentum, taking 22% of all measured media revenues in mature Western markets, versus 12% in fast-growth economies.

MAGNAGlobal, a unit of Interpublic Group, has also released its projections, reporting that the ad sales logged by media owners globally will rise by 4.7% to $427bn this year, and by 5% to $449bn next year.

"More than ever, emerging economies drove global advertising revenue growth in 2011, posting an average +15.0% growth during the year," the company said. "Developed markets, meanwhile, grew at much slower rates."

According to MAGNAGlobal, China is set to overtake Japan as the world's second-largest advertising market next year, as these nations deliver $33.2bn and $32.1bn in media revenues respectively.

To see more information about Warc's own adspend data, click here.

Data sourced from ZenithOptimedia, Mediapost, MAGNAGlobal; additional content by Warc staff